Present day devices and systems for image and motion picture reproduction include many different types: projectors and projection screens, cathode ray tubes (CRT), liquid crystal displays (LCD), and light emitting diode (LED) grid arrays in the form of active billboards.
All of these devices and systems require a predetermined surface to be secured where the images and motion pictures will appear. This surface, which is usually called a screen, is in most cases a continuous, solid object. Because of that, its size is often dictated by the available space and technical realization issues. For many applications, it is desirable that the screen surface area be as large as possible. The capability of a billboard, for example, to capture one's attention is directly proportional to its size.
Furthermore, the brightness of the display will dictate the operational duty cycle on any given day. It is for this reason that conventional outdoor projection systems have a low operational duty cycle (i.e. they are usable only in low light conditions such as during the night time). LED grid arrays are much more effective in being visible even when the sunlight level is at its maximum. Both projection and LED based systems have their drawbacks relating to outdoor screen mounting issues. A projection system could use a building facade as its screen. However, in many cases, it is impossible to project an image onto a building that is occupied. In downtown areas which are crowded with hotels, such as Las Vegas, a majority of the high rising buildings are occupied. Thus, the occupants would be bothered by intense light directed at the building and, at best, the show would have to be limited in both length and how late at night the show could last. Also, a building facade that is mostly covered with windows doesn't make for an optimal projection screen because of the irregularities in its surface and the not so favorable light reflection coefficient of the glass windows. The solution for the surface smoothness would be to cover the building facade with an actual projection screen. This is not desirable because it would completely block the view for the occupants of that building.
Large dynamic LED grid screens face the same problem. They are enclosed in a large, panel shaped, solid object which could weigh thousands of pounds. The mounting requirements for such a device are very stringent which makes them unsuitable for the temporary applications. Permanent mounting of a large panel LED display onto a hotel facade would mean a permanent obstruction of view for the guests.